Conventionally, liquid crystal display devices have been used as displaying sections of television receiving apparatuses.
Each of these liquid crystal display devices incorporate a backlight device as a light source, and a liquid crystal display panel as an optical shutter. The liquid crystal display panel transmits or blocks light emitted from a light source according to an image to be displayed, so as to display the image.
Meanwhile, there are demands for better use efficiency of the light emitted from the light source, in order to attain a brighter display on the liquid crystal display panel.
In response to such demands, various techniques have been proposed. For example, Patent Literature 1 discloses a technique using a lens film made of two lens films (lens sheets) stacked so that their alignment directions of prisms intersect at right angles to each other.
More specifically, Patent Literature 1 discloses a technique in which, of the two lens films, a lens film provided closer to a liquid crystal display element (the liquid crystal display panel) has its alignment direction of the prism arranged parallel to a transmission axis of a polarizing layer through which light enters the liquid crystal display element.
Patent Literature 1
Japanese Patent Application Publication, Tokukaihei, No. 8-22000 A (Publication Date: Jan. 23, 1996)